diff options
Diffstat (limited to 'arch/x86/mm/pat/set_memory.c')
| -rw-r--r-- | arch/x86/mm/pat/set_memory.c | 245 |
1 files changed, 219 insertions, 26 deletions
diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c index 95bc50a8541c..72405d315b41 100644 --- a/arch/x86/mm/pat/set_memory.c +++ b/arch/x86/mm/pat/set_memory.c @@ -32,8 +32,6 @@ #include <asm/pgalloc.h> #include <asm/proto.h> #include <asm/memtype.h> -#include <asm/hyperv-tlfs.h> -#include <asm/mshyperv.h> #include "../mm_internal.h" @@ -75,6 +73,7 @@ static DEFINE_SPINLOCK(cpa_lock); #define CPA_ARRAY 2 #define CPA_PAGES_ARRAY 4 #define CPA_NO_CHECK_ALIAS 8 /* Do not search for aliases */ +#define CPA_COLLAPSE 16 /* try to collapse large pages */ static inline pgprot_t cachemode2pgprot(enum page_cache_mode pcm) { @@ -107,6 +106,18 @@ static void split_page_count(int level) direct_pages_count[level - 1] += PTRS_PER_PTE; } +static void collapse_page_count(int level) +{ + direct_pages_count[level]++; + if (system_state == SYSTEM_RUNNING) { + if (level == PG_LEVEL_2M) + count_vm_event(DIRECT_MAP_LEVEL2_COLLAPSE); + else if (level == PG_LEVEL_1G) + count_vm_event(DIRECT_MAP_LEVEL3_COLLAPSE); + } + direct_pages_count[level - 1] -= PTRS_PER_PTE; +} + void arch_report_meminfo(struct seq_file *m) { seq_printf(m, "DirectMap4k: %8lu kB\n", @@ -124,6 +135,7 @@ void arch_report_meminfo(struct seq_file *m) } #else static inline void split_page_count(int level) { } +static inline void collapse_page_count(int level) { } #endif #ifdef CONFIG_X86_CPA_STATISTICS @@ -213,14 +225,14 @@ within(unsigned long addr, unsigned long start, unsigned long end) return addr >= start && addr < end; } +#ifdef CONFIG_X86_64 + static inline int within_inclusive(unsigned long addr, unsigned long start, unsigned long end) { return addr >= start && addr <= end; } -#ifdef CONFIG_X86_64 - /* * The kernel image is mapped into two places in the virtual address space * (addresses without KASLR, of course): @@ -396,16 +408,49 @@ static void __cpa_flush_tlb(void *data) flush_tlb_one_kernel(fix_addr(__cpa_addr(cpa, i))); } -static void cpa_flush(struct cpa_data *data, int cache) +static int collapse_large_pages(unsigned long addr, struct list_head *pgtables); + +static void cpa_collapse_large_pages(struct cpa_data *cpa) +{ + unsigned long start, addr, end; + struct ptdesc *ptdesc, *tmp; + LIST_HEAD(pgtables); + int collapsed = 0; + int i; + + if (cpa->flags & (CPA_PAGES_ARRAY | CPA_ARRAY)) { + for (i = 0; i < cpa->numpages; i++) + collapsed += collapse_large_pages(__cpa_addr(cpa, i), + &pgtables); + } else { + addr = __cpa_addr(cpa, 0); + start = addr & PMD_MASK; + end = addr + PAGE_SIZE * cpa->numpages; + + for (addr = start; within(addr, start, end); addr += PMD_SIZE) + collapsed += collapse_large_pages(addr, &pgtables); + } + + if (!collapsed) + return; + + flush_tlb_all(); + + list_for_each_entry_safe(ptdesc, tmp, &pgtables, pt_list) { + list_del(&ptdesc->pt_list); + __free_page(ptdesc_page(ptdesc)); + } +} + +static void cpa_flush(struct cpa_data *cpa, int cache) { - struct cpa_data *cpa = data; unsigned int i; BUG_ON(irqs_disabled() && !early_boot_irqs_disabled); if (cache && !static_cpu_has(X86_FEATURE_CLFLUSH)) { cpa_flush_all(cache); - return; + goto collapse_large_pages; } if (cpa->force_flush_all || cpa->numpages > tlb_single_page_flush_ceiling) @@ -414,7 +459,7 @@ static void cpa_flush(struct cpa_data *data, int cache) on_each_cpu(__cpa_flush_tlb, cpa, 1); if (!cache) - return; + goto collapse_large_pages; mb(); for (i = 0; i < cpa->numpages; i++) { @@ -430,6 +475,10 @@ static void cpa_flush(struct cpa_data *data, int cache) clflush_cache_range_opt((void *)fix_addr(addr), PAGE_SIZE); } mb(); + +collapse_large_pages: + if (cpa->flags & CPA_COLLAPSE) + cpa_collapse_large_pages(cpa); } static bool overlaps(unsigned long r1_start, unsigned long r1_end, @@ -1199,6 +1248,161 @@ static int split_large_page(struct cpa_data *cpa, pte_t *kpte, return 0; } +static int collapse_pmd_page(pmd_t *pmd, unsigned long addr, + struct list_head *pgtables) +{ + pmd_t _pmd, old_pmd; + pte_t *pte, first; + unsigned long pfn; + pgprot_t pgprot; + int i = 0; + + addr &= PMD_MASK; + pte = pte_offset_kernel(pmd, addr); + first = *pte; + pfn = pte_pfn(first); + + /* Make sure alignment is suitable */ + if (PFN_PHYS(pfn) & ~PMD_MASK) + return 0; + + /* The page is 4k intentionally */ + if (pte_flags(first) & _PAGE_KERNEL_4K) + return 0; + + /* Check that the rest of PTEs are compatible with the first one */ + for (i = 1, pte++; i < PTRS_PER_PTE; i++, pte++) { + pte_t entry = *pte; + + if (!pte_present(entry)) + return 0; + if (pte_flags(entry) != pte_flags(first)) + return 0; + if (pte_pfn(entry) != pte_pfn(first) + i) + return 0; + } + + old_pmd = *pmd; + + /* Success: set up a large page */ + pgprot = pgprot_4k_2_large(pte_pgprot(first)); + pgprot_val(pgprot) |= _PAGE_PSE; + _pmd = pfn_pmd(pfn, pgprot); + set_pmd(pmd, _pmd); + + /* Queue the page table to be freed after TLB flush */ + list_add(&page_ptdesc(pmd_page(old_pmd))->pt_list, pgtables); + + if (IS_ENABLED(CONFIG_X86_32) && !SHARED_KERNEL_PMD) { + struct page *page; + + /* Update all PGD tables to use the same large page */ + list_for_each_entry(page, &pgd_list, lru) { + pgd_t *pgd = (pgd_t *)page_address(page) + pgd_index(addr); + p4d_t *p4d = p4d_offset(pgd, addr); + pud_t *pud = pud_offset(p4d, addr); + pmd_t *pmd = pmd_offset(pud, addr); + /* Something is wrong if entries doesn't match */ + if (WARN_ON(pmd_val(old_pmd) != pmd_val(*pmd))) + continue; + set_pmd(pmd, _pmd); + } + } + + if (virt_addr_valid(addr) && pfn_range_is_mapped(pfn, pfn + 1)) + collapse_page_count(PG_LEVEL_2M); + + return 1; +} + +static int collapse_pud_page(pud_t *pud, unsigned long addr, + struct list_head *pgtables) +{ + unsigned long pfn; + pmd_t *pmd, first; + int i; + + if (!direct_gbpages) + return 0; + + addr &= PUD_MASK; + pmd = pmd_offset(pud, addr); + first = *pmd; + + /* + * To restore PUD page all PMD entries must be large and + * have suitable alignment + */ + pfn = pmd_pfn(first); + if (!pmd_leaf(first) || (PFN_PHYS(pfn) & ~PUD_MASK)) + return 0; + + /* + * To restore PUD page, all following PMDs must be compatible with the + * first one. + */ + for (i = 1, pmd++; i < PTRS_PER_PMD; i++, pmd++) { + pmd_t entry = *pmd; + + if (!pmd_present(entry) || !pmd_leaf(entry)) + return 0; + if (pmd_flags(entry) != pmd_flags(first)) + return 0; + if (pmd_pfn(entry) != pmd_pfn(first) + i * PTRS_PER_PTE) + return 0; + } + + /* Restore PUD page and queue page table to be freed after TLB flush */ + list_add(&page_ptdesc(pud_page(*pud))->pt_list, pgtables); + set_pud(pud, pfn_pud(pfn, pmd_pgprot(first))); + + if (virt_addr_valid(addr) && pfn_range_is_mapped(pfn, pfn + 1)) + collapse_page_count(PG_LEVEL_1G); + + return 1; +} + +/* + * Collapse PMD and PUD pages in the kernel mapping around the address where + * possible. + * + * Caller must flush TLB and free page tables queued on the list before + * touching the new entries. CPU must not see TLB entries of different size + * with different attributes. + */ +static int collapse_large_pages(unsigned long addr, struct list_head *pgtables) +{ + int collapsed = 0; + pgd_t *pgd; + p4d_t *p4d; + pud_t *pud; + pmd_t *pmd; + + addr &= PMD_MASK; + + spin_lock(&pgd_lock); + pgd = pgd_offset_k(addr); + if (pgd_none(*pgd)) + goto out; + p4d = p4d_offset(pgd, addr); + if (p4d_none(*p4d)) + goto out; + pud = pud_offset(p4d, addr); + if (!pud_present(*pud) || pud_leaf(*pud)) + goto out; + pmd = pmd_offset(pud, addr); + if (!pmd_present(*pmd) || pmd_leaf(*pmd)) + goto out; + + collapsed = collapse_pmd_page(pmd, addr, pgtables); + if (collapsed) + collapsed += collapse_pud_page(pud, addr, pgtables); + +out: + spin_unlock(&pgd_lock); + return collapsed; +} + static bool try_to_free_pte_page(pte_t *pte) { int i; @@ -1944,19 +2148,6 @@ static inline int cpa_clear_pages_array(struct page **pages, int numpages, CPA_PAGES_ARRAY, pages); } -/* - * __set_memory_prot is an internal helper for callers that have been passed - * a pgprot_t value from upper layers and a reservation has already been taken. - * If you want to set the pgprot to a specific page protocol, use the - * set_memory_xx() functions. - */ -int __set_memory_prot(unsigned long addr, int numpages, pgprot_t prot) -{ - return change_page_attr_set_clr(&addr, numpages, prot, - __pgprot(~pgprot_val(prot)), 0, 0, - NULL); -} - int _set_memory_uc(unsigned long addr, int numpages) { /* @@ -2122,7 +2313,8 @@ int set_memory_rox(unsigned long addr, int numpages) if (__supported_pte_mask & _PAGE_NX) clr.pgprot |= _PAGE_NX; - return change_page_attr_clear(&addr, numpages, clr, 0); + return change_page_attr_set_clr(&addr, numpages, __pgprot(0), clr, 0, + CPA_COLLAPSE, NULL); } int set_memory_rw(unsigned long addr, int numpages) @@ -2149,7 +2341,8 @@ int set_memory_p(unsigned long addr, int numpages) int set_memory_4k(unsigned long addr, int numpages) { - return change_page_attr_set_clr(&addr, numpages, __pgprot(0), + return change_page_attr_set_clr(&addr, numpages, + __pgprot(_PAGE_KERNEL_4K), __pgprot(0), 1, 0, NULL); } @@ -2422,7 +2615,7 @@ static int __set_pages_np(struct page *page, int numpages) .pgd = NULL, .numpages = numpages, .mask_set = __pgprot(0), - .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW), + .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY), .flags = CPA_NO_CHECK_ALIAS }; /* @@ -2509,7 +2702,7 @@ int __init kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address, .pgd = pgd, .numpages = numpages, .mask_set = __pgprot(0), - .mask_clr = __pgprot(~page_flags & (_PAGE_NX|_PAGE_RW)), + .mask_clr = __pgprot(~page_flags & (_PAGE_NX|_PAGE_RW|_PAGE_DIRTY)), .flags = CPA_NO_CHECK_ALIAS, }; @@ -2552,7 +2745,7 @@ int __init kernel_unmap_pages_in_pgd(pgd_t *pgd, unsigned long address, .pgd = pgd, .numpages = numpages, .mask_set = __pgprot(0), - .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW), + .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY), .flags = CPA_NO_CHECK_ALIAS, }; |